Abstract

Air pollutants may be transported over several hundred kilometer ranges, across continents, oceans (intercontinental), hemispheres, or even globally, depending on lifetime and other properties. Transported emissions include primary pollutants emitted from industry and vehicles (e.g., nitric oxide) and natural pollutants emitted from forest fires (e.g., soot). Also secondary pollutants (e.g., ozone) that are formed near the source region undergo transport. Recent advances in understanding atmospheric transport pathways, source-receptor relationships, and transformation of pollutants during transport are described.